Soundcloud integration design is not centered and too big

Since the new Ghost update the design of soundcloud cards is not correct anymore, see

I’d expect it to behave similar as before: centered, but not so big and not overlapping the right margin.

This worked before, but the preview in edit mode was broken since the new version, so I re-added the soundcloud links and now the design changed.

I’d consider this as bug, but is there a css fix I can apply? I could not find a workaround, still trying.